Improvement in pinions



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vineit Aw. BLANGHARD, or BRinPonT, VERMONT; l

Laim Patent No. 102,363, dated april 26, 1870.

IMPROVEMENT IN rmroNs.

The Schedule referred to in. these Lettera Patent and making part of thesame.

To all whom ttmay concern.

Be it known that I, VIEGIL W. BLANCHARD, of the' town of Bridport, inthe county of Addison and State of Vermont, have invented certain newand useful Improveinent in Pinions; and I do hereby declai'e that thefollowing is a. full, clear, and exact description thereof, referencebeing had to the accompanying drawings and to the letters of referencem'arked thereon which form a part of this specification.

In order to enable others skilled in the art to make and use the same, Iwill now proceed to describe its construction and operation, referringto the annexed drawings, in which- Figure 1 is a perspective of thepinion, and

Figure 2 is a longitudinal half of the pinion. i

A represents the bearing at the small extremity.

B, the ange at the small extremity.

Q is the large extremity orliead of the, pinion, having a circularopening to t the shaft to which it may be applied.

D D represent the teeth, four in number.

It will be observed that, by longitudinally dividing two of the teeth intheir center, one on each side, a pattern is producedfor molding apinionwith four teeth, that may be laterally drawn from the sand, whichposition of the pattern in the sand and direction of draft admits of theflange B and. journal or bearing A being attached to its smallextremity,

which could not be done if the pattern was in one piece and drawnvertically from the sand in molding,

which is now the only and usual method' of molding pinions.

The circular opening in the head or large extreinity C affords a meansof attaching the pinion to the shaft to which it is desirable tocommunicate motion.

A beaiingLsurface or journal is requisite on the shaft to which thepinion is' attached near the point of attachment.

If the shaft to which it is desirable to communicate motion is short, itmay be cast solid, with the head or large extremity C, in which case thecircular opening would not be necessary.

It will be particularly` observed that the shaft to which the pinion isattached does not extend into that section of the pinion that isoccupied by the teeth. -It will also be observed that thepseotion of thepinion occupied by the teeth D D contains, beside the teeth, only averysmall central core of metal, just sucient to give a firm attachment tothe base of the teeth longitudinally, and to join them together.

This core, with the'teeth, connects the head or large extremity C withthe iange B, and it is to this section that the teeth of the propellinggear are applied.'

Now, by bringing the pitch line of the teeth so.

near the longitudinal central line of the pinion, a strong, durablepinion of four teeth, of very small size, is obtained. l

A pinion with vthe pitch line of its teeth so near the center of theshaft to which it is applied as this inust necessarily be, must, ofnecessity, have a beail iiigoi journal at its small extremity to runsmoothly and be durable. This is provided for by means .of

the iiange and journal or bearing A-springing from the saine. The centerof the journal or bearing A, it will be observed, must be in aline withthe center of the shaft to which the pinion is applied.- l

In the practical operation of this invention the pinion, if its head Cis not cast solid with the shaft to which it is desirable to communicatemotion, is rmly secuied by the circular opening in the head G to saidshaft.

This shaft should be provided, near the point of attachment of thepinion, with a bearing-surface or journal. The small extremity 'A of thepinion should `be tted into a bearingfsurface, or jouriialed on alineWtli the shaft to which it is attached.

vThe journal on the shaft, and that ou the small extremity of thepinion, should be provided with accurate bearing-surfaces or boxes.Power may then be-applied by -means of a suitable gear-wheel to the vteeth of' the pinion, producing a rotary motion in the vshaft to whichthe pinion is applied.

Having thus fully described my invention, What I claim as new, anddesire to secure by Letters Patent, is-

1.' Forming a pinion provided at its small extreni ity with a flange tostrengthen the teeth, and with a journal springipg from said flange,substantially as and for the purpose set forth.

2. Forming avpinion of four teeth, .provided at its small extremity witha journal of greater diameter than its greatestjdiameter'at the pitchline of its teeth,su stantially as and for the purposes specified.

3. Fori ing a pinion having, iu the section occulpied by th teeth, onlythe teeth and a central core.

of metal, of sufcient size to join the teeth longitudinally at thfhrbase, substantially as and for the purpose described\ A 4.- The head Gand teeth D D, in combination with the flange B' and \jouinal A, in apinion composed of cast metal, substan 'rally as 'and for the purposesdescribed.

In testimony that I claim the foregoing as my own,

l affix my signature in the presence of two witnesses.

i VIRGIL W. BLANCHARD.

Witnesses:

'N. S. BENNETT,

